An example of a hopper coin feeder of the horizontal disc type is that described in Patent Specification WO 99/33030 of Scan Coin AB. The coin feeder is part of a coin sorter, the SC Active 2200, which is a relatively bulky high speed machine for handling large quantities of coins in banks or cash centres, for example. The present invention stems from work to produce relatively compact coin handling equipment that can be used, for example, in a retail outlet in association with a till. Such equipment may operate at slower speeds than that of the SC2200 and accordingly this can involve smaller angular velocities of coins in the hopper.
When coins are input to a hopper coin feeder in a batch ideally the coins must be separated into a single layer so that they can be fed one by one to a coin discriminator. It is desirable for coins to be presented individually to the discriminator to allow them to be correctly sorted and/or counted. If the coins are not separated in this way it is possible for ‘piggyback’ coins (that is, one coin with one or more other coins riding on top of it) to make discrimination and/or counting of coins inaccurate.
It is known from WO 99/33030 for example, to provide a hopper comprising a stationary rigid cylindrical (or part-cylindrical) wall, which defines the principal coin-holding zone of the hopper and which has a stepped lower edge to define with the upper face of the horizontal disc a coin outlet gap from said zone, the gap being substantially the same height as the thickness of the thickest coin to be handled. When in use, the coins are carried by the rotating disc they tend to move outwardly under the influence of centrifugal force to impact the wall, and the stepped lower edge acts to scrape off the top layer of coins, only allowing coins with a thickness less than the height of the outlet gap to pass beneath the wall. Coins which can be fed by such a hopper feeder are obviously limited to those having a thickness which is less than the height of the outlet gap.
This arrangement is not completely satisfactory when feeding a mixed batch of coins, as not all coins are the same thickness. In a case where the combined thickness of two thin coins is less than the thickness of the thickest coin which can be fed through the outlet gap, it is possible for two thin coins to pass under the wall on top of each other. In addition to this, it is possible for two such piggyback coins to become jammed within the gap. Such a jam may be acceptable in a bank or cash centre setting, where the machine operatives are relatively skilled and are capable of quickly clearing the jam. It is not satisfactory, however, in a retail setting. In this situation a coin feeder is desired to be easy to operate and relatively fault free, as well as being capable of presenting a single layer of coins to a coin discriminator in order to allow the coins to be accurately counted and/or sorted.